1. There's a whole convoluted pinball metaphor going on here...Nobody real in his life, just the pinball machine to serve as a lover and the noise of the steel balls for conversation

2. This is an unusual turn of phrase in French, but the meaning seems clear that he's describing someone who prefers to keep themself to themself, not exactly an introvert but a private person. Francis has said in interviews that he wrote the song so he wouldn't have to keep explaining himself but that unfortunately it just prompted more questions!